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Repairing a Cobra 29. Help.

longhaireddwb

W9WDX Amateur Radio Club Member
Oct 8, 2008
555
30
38
Colorado Springs, CO
Got this older Cobra 29 for free. It had a broken leg on the audio chip so I replaced the chip and now it works. So not much into this one. Someone had molested this radio in my terms. Put a T.B., Echo board and noise toy. I've managed to get most of it back the way it should be except for the switch for the NB/ANL. Looking at schematics is not helping me at all. I'm a bit new to reading all the squiggly lines. ha.

What I could use for help is to know how to rewire the switch. I can tell from what point on the board the wires come from (schematics) but...
the switch has 8 spots to solder too. I understand that one side of 4 spots are separate from the other 4. Also that in the lower position, the two lowest spots are closed, in middle position the two middle spots are closed and the same for when in the upper position.

Can someone tell me if a jumper needs to be put across any of these and what wire goes where? No wires going to the switch now because they were used for the noise toy. Can you help this truck driver/sort-of radio repairing guy to figure this out?
Thanks.
 

The two wires for the ANL side of the switch work differently than the NB side of the switch.

It sounds backwards, but closing the ANL side turns the ANL OFF. And breaking the circuit between those two wires turns the ANL (only) ON.

The NB is more intuitive. Closing that side of the switch turns the noise blanker on. Breaking the circuit between those two wires shuts the blanker off.

There are a dozen and a half different Cobra radios that have had the model number "29" put on them. Pinning down which version you have would go a long way to getting detailed info like the wire colors for ANL and NB.

Cobra got pretty crazy with suffix letters following the digits "29", with "XLR", "GTL", "LTD", "LTD-WX/ST" etc.

Different wire color schemes in every one, more or less.

73
 
Well, This is a Cobra 29LTD with the side mic. No WX or ST or any of that stuff. As far as wire colors, that beyond correct as this radio had been hacked up pretty badly by someone that shouldn't have been messing with it.

I got part of the NB/ANL working but its not changing when I go from NB to NB/ANL. Only the channel display dims, not the meter light and I still got about 6 wires sticking out of the board. I'll get it figured out now that I have better info. Its just going to take a few more hours tracing wires with these old eyes.

Thanks for the help gentlemen. I hate when folk go messing with things they really shouldn't be doing. Thanks to the internet, everyone think they are an electronic wiz. Not that I'm a bunch better but at least I got an idea of what I'm doing!
73
 

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